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921.
Katsura Maeda-Sano Mari Gotoh Toshiro Morohoshi Takao Someya Hiromu Murofushi Kimiko Murakami-Murofushi 《Biochimica et Biophysica Acta (BBA)/Molecular and Cell Biology of Lipids》2014,1841(9):1256-1263
Cyclic phosphatidic acid (cPA) is a naturally occurring phospholipid mediator and an analog of the growth factor-like phospholipid lysophosphatidic acid (LPA). cPA has a unique cyclic phosphate ring at the sn-2 and sn-3 positions of its glycerol backbone. We showed before that a metabolically stabilized cPA derivative, 2-carba-cPA, relieved osteoarthritis pathogenesis in vivo and induced hyaluronic acid synthesis in human osteoarthritis synoviocytes in vitro. This study focused on hyaluronic acid synthesis in human fibroblasts, which retain moisture and maintain health in the dermis. We investigated the effects of cPA and LPA on hyaluronic acid synthesis in human fibroblasts (NB1RGB cells). Using particle exclusion and enzyme-linked immunosorbent assays, we found that both cPA and LPA dose-dependently induced hyaluronic acid synthesis. We revealed that the expression of hyaluronan synthase 2 messenger RNA and protein is up-regulated by cPA and LPA treatment time dependently. We then characterized the signaling pathways up-regulating hyaluronic acid synthesis mediated by cPA and LPA in NB1RGB cells. Pharmacological inhibition and reporter gene assays revealed that the activation of the LPA receptor LPAR1, Gi/o protein, phosphatidylinositol-3 kinase (PI3K), extracellular-signal-regulated kinase (ERK), and cyclic adenosine monophosphate response element-binding protein (CREB) but not nuclear factor κB induced hyaluronic acid synthesis by the treatment with cPA and LPA in NB1RGB cells. These results demonstrate for the first time that cPA and LPA induce hyaluronic acid synthesis in human skin fibroblasts mainly through the activation of LPAR1-Gi/o followed by the PI3K, ERK, and CREB signaling pathway. 相似文献
922.
Claire J Greenhill Gareth W Jones Mari A Nowell Zarabeth Newton Ann K Harvey Abdul N Moideen Fraser L Collins Anja C Bloom Rebecca C Coll Avril AB Robertson Matthew A Cooper Marcela Rosas Philip R Taylor Luke A O’Neill Ian R Humphreys Anwen S Williams Simon A Jones 《Arthritis research & therapy》2014,16(4)
Introduction
Activation of the inflammasome has been implicated in the pathology of various autoinflammatory and autoimmune diseases. While the NLRP3 inflammasome has been linked to arthritis progression, little is known about its synovial regulation or contribution to joint histopathology. Regulators of inflammation activation, such as interleukin (IL)-10, may have the potential to limit the inflammasome-driven arthritic disease course and associated structural damage. Hence, we used IL-10-deficient (IL-10KO) mice to assess NLRP3 inflammasome-driven arthritic pathology.Methods
Antigen-induced arthritis (AIA) was established in IL-10KO mice and wild-type controls. Using histological and radiographic approaches together with quantitative real-time PCR of synovial mRNA studies, we explored the regulation of inflammasome components. These were combined with selective blocking agents and ex vivo investigative studies in osteoclast differentiation assays.Results
In AIA, IL-10KO mice display severe disease with increased histological and radiographic joint scores. Here, focal bone erosions were associated with increased tartrate-resistant acid phosphatase (TRAP)-positive cells and a localized expression of IL-1β. When compared to controls, IL-10KO synovium showed increased expression of Il1b, Il33 and NLRP3 inflammasome components. Synovial Nlrp3 and Casp1 expression further correlated with Acp5 (encoding TRAP), while neutralization of IL-10 receptor signaling in control mice caused increased expression of Nlrp3 and Casp1. In ex vivo osteoclast differentiation assays, addition of exogenous IL-10 or selective blockade of the NLRP3 inflammasome inhibited osteoclastogenesis.Conclusions
These data provide a link between IL-10, synovial regulation of the NLRP3 inflammasome and the degree of bone erosions observed in inflammatory arthritis.Electronic supplementary material
The online version of this article (doi:10.1186/s13075-014-0419-y) contains supplementary material, which is available to authorized users. 相似文献923.
Federico Pietrocola Shoaib Ahmad Malik Guillermo Mariño Erika Vacchelli Laura Senovilla kariman chaba 《Cell cycle (Georgetown, Tex.)》2014,13(12):1987-1994
Epidemiological studies and clinical trials revealed that chronic consumption coffee is associated with the inhibition of several metabolic diseases as well as reduction in overall and cause-specific mortality. We show that both natural and decaffeinated brands of coffee similarly rapidly trigger autophagy in mice. One to 4 h after coffee consumption, we observed an increase in autophagic flux in all investigated organs (liver, muscle, heart) in vivo, as indicated by the increased lipidation of LC3B and the reduction of the abundance of the autophagic substrate sequestosome 1 (p62/SQSTM1). These changes were accompanied by the inhibition of the enzymatic activity of mammalian target of rapamycin complex 1 (mTORC1), leading to the reduced phosphorylation of p70S6K, as well as by the global deacetylation of cellular proteins detectable by immunoblot. Immunohistochemical analyses of transgenic mice expressing a GFP–LC3B fusion protein confirmed the coffee-induced relocation of LC3B to autophagosomes, as well as general protein deacetylation. Altogether, these results indicate that coffee triggers 2 phenomena that are also induced by nutrient depletion, namely a reduction of protein acetylation coupled to an increase in autophagy. We speculate that polyphenols contained in coffee promote health by stimulating autophagy. 相似文献
924.
Mariángeles Noto Llana Sebastián Hernán Sarnacki María del Rosario Aya Casta?eda María Carolina Pustovrh Alejandra Sonia Gartner Fernanda Roxana Buzzola María Cristina Cerquetti Mónica Nancy Giacomodonato 《PloS one》2014,9(11)
Foodborne diseases caused by Salmonella enterica serovar Enteritidis (S. Enteritidis) are a significant health problem. Pregnancy, state of immunological tolerance, is a predisposing condition for the development of infections with intracellular pathogens. Salmonella species can cause pregnancy complications such as chorioamnionitis, transplacental fetal infection, pre term labor, abortions, neonatal and maternal septicemia. However, the specific mechanisms by which Salmonella infections trigger these alterations are not clear. In the present work, using a self-limiting enterocolitis murine model, we show that the ingestion of a low dose of S. Enteritidis at late stages of pregnancy (day 15 of gestation) is sufficient to induce massive maternal infection. We found that Salmonella infection leads to 40% of pre term delivery, 33% of abortion and fetal growth restriction. Placental dysfunction during S. Enteritidis enterocolitis was confirmed through cellular infiltration and hypoxia markers (MPO activity and COX-1 and COX-2 expression, respectively). Apoptosis in placental tissue due to Salmonella infection was also evident at day 18 of gestation when investigated by morphometric procedure, DNA fragmentation and Fas/FasL expression. Also, the expression of IFN-γ, TNF-α, IL-17 and IL-10 was up regulated in response to Salmonella not only in placenta, but also in amniotic fluid and maternal serum. Altogether, our results demonstrate that S. Enteritidis enterocolitis during late stages of gestation causes detrimental effect on pregnancy outcome. 相似文献
925.
Maíra Mendes dos Santos Maria Ines Quintana Fernanda Gon?alves Moreira José Geraldo Vernet Taborda Jair de Jesus Mari Sérgio Baxter Andreoli 《PloS one》2014,9(11)
Objective
To analyze the association between drug (DAD) and alcohol (AAD) abuse and dependency and criminal and clinical background by gender of prisoners in São Paulo, Brazil.Method
Cross-sectional study, random sample stratified by administrative district, from which prisons and prisoners were selected via random, multistage sampling. Psychiatric diagnoses were made with the CIDI 2.1. Lifetime prevalence and 95% CI were calculated and adjusted via analysis of complex samples. Multinomial logistic regression analysis was carried out with four categories of dependent variables: presence AAD; presence DAD; presence of another mental disorder; no mental disorders. For female alcohol and drug abuse and dependency (ADAD) were combined into a single category.Results
The sample was composed by 1809 interviewed prisoners (1192 men and 617 women). Prevalence of DAD and AAD was 25.2% and 15.6%, respectively, among female prisoners, and 26.5% and 18.5% among males. Male prisoners with DAD were more likely to have a criminal record as an adolescent (OR 2.17), to be a repeat offender (OR 2.85), and to have committed a property crime (OR 2.18). Prisoners with AAD were repeat offenders (OR 2.18). Among female prisoners, ADAD was associated with repeat offenses (OR 3.39), a criminal record as an adolescent (OR 9.24), a clinical or infectious condition (OR 5.09), another health problem (OR 3.04), and violent crime (OR 2.5).Conclusion
The study confirmed an association between drug-use disorders and the criminal and clinical background in the study population. Prisoners with such disorders were more likely to be repeat offenders and to have a criminal record as adolescents. Among female prisoners disorders were also associated with violent crime and health problems, while among males they were associated with property crime. These patterns in clinical and criminal backgrounds illustrate the need for social rehabilitation programs and specific medical treatment for prison populations. 相似文献926.
Mari Nekohashi Mana Ogawa Takuo Ogihara Kyoko Nakazawa Hisanori Kato Takumi Misaka Keiko Abe Shoko Kobayashi 《PloS one》2014,9(5)
Niemann–Pick C1-Like 1 (NPC1L1) mediates cholesterol absorption, and ezetimibe is a potent NPC1L1 inhibitor applicable for medication of hypercholesterolemia. Epidemiological studies demonstrated that consumption of polyphenols correlates with a decreased risk for atherosclerosis due to their antioxidant effect. This activity can hardly be attributable to the antioxidant activity only, and we hypothesized that polyphenols inhibit intestinal transport of cholesterol. We elucidated the kinetic parameters of intestinal cholesterol absorption, screened several polyphenols for their ability to specifically inhibit intestinal cholesterol absorption, and determined the inhibitory effects of selected flavonoids in vitro and in vivo. The concentration-dependent uptake of cholesterol by Caco-2 cells obeyed a monophasic saturation process. This indicates the involvement of an active-passive transport, i.e., NPC1L1. Parameters of cholesterol uptake by Caco-2 cells were as follows: J
max, K
t, and K
d were 6.89±2.96 19.03±11.58 µM, and 0.11±0.02 pmol/min/mg protein, respectively. Luteolin and quercetin inhibited cholesterol absorption by Caco-2 cells and human embryonic kidney 293T cells expressing NPC1L1. When preincubated Caco-2 cells with luteolin and quercetin before the assay, cholesterol uptake significantly decreased. The inhibitory effects of these flavonoids were maintained for up to 120 min. The level of inhibition and irreversible effects were similar to that of ezetimibe. Serum cholesterol levels significantly decreased more in rats fed both cholesterol and luteolin (or quercetin), than in those observed in the cholesterol feeding group. As quercetin induced a significant decrease in the levels of NPC1L1 mRNA in Caco-2 cells, the in vivo inhibitory effect may be due to the expression of NPC1L1. These results suggest that luteolin and quercetin reduce high blood cholesterol levels by specifically inhibiting intestinal cholesterol absorption mediated by NPC1L1. 相似文献
927.
Paola Nicolini Michele M. Ciulla Gabriella Malfatto Carlo Abbate Daniela Mari Paolo D. Rossi Emanuela Pettenuzzo Fabio Magrini Dario Consonni Federico Lombardi 《PloS one》2014,9(5)
Background
Mild cognitive impairment (MCI) is set to become a major health problem with the exponential ageing of the world''s population. The association between MCI and autonomic dysfunction, supported by indirect evidence and rich with clinical implications in terms of progression to dementia and increased risk of mortality and falls, has never been specifically demonstrated.Aim
To conduct a comprehensive assessment of autonomic function in subjects with MCI by means of power spectral analysis (PSA) of heart rate variability (HRV) at rest and during provocative manoeuvres.Methods
This cross-sectional study involved 80 older outpatients (aged ≥65) consecutively referred to a geriatric unit and diagnosed with MCI or normal cognition (controls) based on neuropsychological testing. PSA was performed on 5-minute electrocardiographic recordings under three conditions—supine rest with free breathing (baseline), supine rest with paced breathing at 12 breaths/minute (parasympathetic stimulation), and active standing (orthosympathetic stimulation)—with particular focus on the changes from baseline to stimulation of indices of sympathovagal balance: normalized low frequency (LFn) and high frequency (HFn) powers and the LF/HF ratio. Blood pressure (BP) was measured at baseline and during standing. Given its exploratory nature in a clinical population the study included subjects on medications with a potential to affect HRV.Results
There were no significant differences in HRV indices between the two groups at baseline. MCI subjects exhibited smaller physiological changes in all three HRV indices during active standing, consistently with a dysfunction of the orthosympathetic system. Systolic BP after 10 minutes of standing was lower in MCI subjects, suggesting dysautonomia-related orthostatic BP dysregulation.Conclusions
Our study is novel in providing evidence of autonomic dysfunction in MCI. This is associated with orthostatic BP dysregulation and the ongoing follow-up of the study population will determine its prognostic relevance as a predictor of adverse health outcomes. 相似文献928.
Objectives
Cancer and metabolic bone diseases can alter the SUV. SUV values have never been measured from healthy skeletons in NaF18-PET/CT bone scans. The primary aim of this study was to measure the SUV values from normal skeletons in NaF18-PET/CT bone scans.Methods
A retrospective study was carried out involving NaF18- PET/CT bone scans that were done at our institution between January 2010 to May 2012. Our excluding criteria was patients with abnormal real function and patients with past history of cancer and metabolic bone diseases including but not limited to osteoporosis, osteopenia and Paget’s disease. Eleven studies met all the criteria.Results
The average normal SUVmax values from 11 patients were: cervical vertebrae 6.84 (range 4.38–8.64), thoracic vertebrae 7.36 (range 6.99–7.66), lumbar vertebrae 7.27 (range 7.04–7.72), femoral head 2.22 (range 1.1–4.3), humeral head 1.82 (range 1.2–2.9), mid sternum 5.51 (range 2.6–8.1), parietal bone 1.71 (range 1.3–2.4).Conclusion
According to our study, various skeletal sites have different normal SUV values. SUV values can be different between the normal bones and bones with tumor or metabolic bone disease. SUV can be used to quantify NaF-18 PET/CT studies. If the SUV values of the normal skeleton are known, they can be used in the characterization of bone lesions and in the assessment of treatment response to bone diseases. 相似文献929.
Adriano R. Lima Marcelo F. Mello Sérgio B. Andreoli Victor Fossaluza Célia M. de Araújo Andrea P. Jackowski Rodrigo A. Bressan Jair J. Mari 《PloS one》2014,9(1)